MJTelco, a startup with innovative optical communications hardware patents, is scaling its proof-of-concept (PoC) project to support over 50,000 installations. They require a schema in Google Bigtable for historical analysis of the last 2 years of records, with each record sent every 15 minutes containing a unique device identifier and a data record. The most common query is for all data for a given device on a given day. Which schema should you use?